Investigation of microbial composition and functional characterization of Zangqu using high throughput sequencing

Abstract

Zangqu is a saccharifying starter used in the production of highland barley wine, which is a traditional Chinese liquor. The objective of this study was to explore microbial composition and function of Zangqu. 16 Zangqu samples were collected from seven different locations in Tibet were analyzed microbial communities using high throughput sequencing technology. The sequenceing analysis revealed 1 340 734 fungal Internal Transcribed Spacer (ITS) reads and 737 185 high quality bacterial 16S rDNA sequences, which were used for taxonomic classification. A total of four fungal and six bacterial phyla were predominantly present in Zangqu samples. Saccharomycopsis, Rhizopus, and Aspergillus were the most abundantly present fungal genera, and Lactobacillus and Leuconostoc were the most abundantly present bacterial genera. The saccharifying ability and protease activity are widely used to evaluate the quality of Zangqu. 57 strains were isolated from all samples using traditional culture medium screening method, as well as molecular biological analysis. Rhizopus oryzaeM12 had the highest saccharifying ability, which was 1382 ± 77.38 mg/g min.Bacillus amyloliquefaciensQ4 had the highest protease activity, which was 1035.56 ± 40.09 μg/g min. We hope that our research analysis can provide statistical support for establishing microbial database and for screening of functional microorganisms.